Arkansas vegetable growers evaluating freeze damage
Apr 11, 2007 10:07 AM,
By Mary F. Hightower
Arkansas Extension Communication Specialist
It’s too early to tell how much damage a weekend of freezing weather has wrought on Arkansas’ vegetable crops, says Craig Andersen, Extension horticulture specialist-vegetables.
“At this point the best advice that can be given to growers and gardeners is to have patience for several days before doing anything,” he said. The types and extent of damage depend on the type of freeze that affected a particular garden.
“The freeze of Friday night/Saturday morning was an ‘advective’ freeze associated with cold blowing wind. These types of freezes are the most difficult to protect against and tend to have the most extensive damage throughout the plant canopy,” Andersen said.
“The Saturday night/Sunday morning freeze tended to be a radiation freeze with low or non-existent wind speeds associated with clear skies and rapid loss of heat from the plant zone.”
Gardeners can protect their crops from radiation freeze with hot caps, row covers, Walls o’ Water and by simply choosing locations that tend to be frost-free. However, in areas where temperatures fell below 24 degrees, even protected plants may show damage.
“Susceptible plants such as Irish potatoes will have blackened leaves and stems and the above-ground parts of the plants were severely damaged,” Andersen said. “Wait seven to 10 days to see if new shoots re-emerge from the seed piece. In most cases removing damaged plant tissue is not necessary and may cause further injury.”
Here’s a look at the damage crop-by-crop:
Onions and garlic — May have some burn on the leaves but should recover. “The damage to onions shows up later with the development of a flower stalk,” he said. “Just use these onions first as they have poor storage characteristics.”
Corn, green beans, tomatoes — Depending on location, these may be severely damaged and beyond recovery. “Three to five days will indicate the survivability of these plants,” Andersen said. “It is still early and these crops can be replanted with some delay in harvest date and loss of yield.”
Squash, cucumbers — If damaged by a radiation freeze may lose some of the outer leaves but may recover if the crown of the plant wasn’t damaged.
In southwest Arkansas, Miller County Extension Agent John Turner said he had received calls about squash and cucumbers affected by the freeze. “Growers need to hang on and not panic,” he said, adding with a laugh that “whatever is left will be tough. After a few days of sun, we’ll be able to tell them whether they’ll need to pull the plants and start over,” he said.
Peppers — Replant these, Andersen said.
Greens, lettuce, radishes, broccoli and cabbage — These may have damage from leaf burn on the outer leaves to entire plant death. “It’s best to wait and see what will happen with these plants,” he said.
Growers who participate in crop insurance programs should document the severity and extent of crop damage with pictures over the next three to five days.
“They will need to contact their USDA Risk Management Agency for further instructions,” Andersen said.
Andersen offered one last bit of consolation and warning. “It’s only April 9. It’s early and for most crops in the garden things can be replanted,” he said. “There may be some delay in when the crop is harvested, and yield may suffer, but freezes at this time of year are not uncommon. In fact we even have a term for it: ‘blackberry winter’.”
e-mail: mhightower@uaex.edu
